The objective of this project is to determine the factors which govern the level and nature of binding between aromatic amine carcinogens and nucleic acids. The binding of N-acetoxy-N-arylacetamides in vitro and of N-arylacetamides in vivo to nucleic acids will be determined for a variety of aryl substituents and in at least two different target tissues. The products of reaction between esters of N-arylhydroxamic acids and nucleosides will be isolated and identified, in order to determine the nature of the binding to total nucleic acid. The products of decomposition of such esters in simple solvolysis systems will also be determined to aid in understanding the reactive characteristics of the intermediates. Where possible, interpretation of the results will be cast in the form of molecular orbital descriptions of the reactive intermediates. To date, the major products of reaction between guanosine and adenosine and esters of N-hydroxy-2-acetamidophenanthrene have been identified. A solvolysis study of N-acetoxy-4-acetamidostilbene has been completed, which offers clues to the structures of the as yet unidentified adducts from the reactions of this compound with guanosine, adenosine and cytidine. Molecular orbital calculations carried out to date suggest that variations in the reactions of esters of different N-arylhydroxamic acids are explainable in terms of reactivity distribution within the intermediate nitrenium ions.